As used herein, the term “wireless device” (alternatively “WD”) might in some cases refer to mobile devices such as mobile telephones, personal digital assistants, handheld or laptop computers, and similar devices that have telecommunications capabilities. Such a WD might include a device and its associated removable memory module, such as but not limited to a Universal Integrated Circuit Card (UICC) that includes a Subscriber Identity Module (SIM) application, a Universal Subscriber Identity Module (USIM) application, or a Removable User Identity Module (R-UIM) application. Alternatively, such a WD might include the device itself without such a module. In other cases, the term “WD” might refer to devices that have similar capabilities but that are not transportable, such as desktop computers, set-top boxes, or network appliances. The term “WD” can also refer to any hardware or software component that can terminate a communication session for a user. Also, the terms “wireless device”, “WD”, “user equipment,” “UE,” “user agent,” “UA,” “user device,” and “mobile device” might be used synonymously herein.
As telecommunications technology has evolved, more advanced network access equipment has been introduced that can provide services that were not possible previously. This network access equipment might include systems and devices that are improvements of the equivalent equipment in a traditional wireless telecommunications system. Such advanced or next generation equipment may be included in evolving wireless communications standards, such as long-term evolution (LTE). For example, an LTE system might include an Evolved Universal Terrestrial Radio Access Network (E-UTRAN) node B (eNB), a wireless access point, or a similar component rather than a traditional base station. Any such component may be referred to herein as a base station or a BS. That is, the term “base station” as used herein may be a generic term that encompasses macro cellular base stations and small cell base stations. Such a component may also be referred to herein as an access node or a network element.
Any set of cells that includes one or more cells with a smaller coverage area than the typical coverage area of a traditional eNB may be referred to herein as a small cell deployment. A cell with the relatively large coverage area provided by a traditional eNB may be referred to herein as a macro cell. A cell with a relatively smaller coverage area than a macro cell may be referred to herein as a small cell, a micro cell, a pico cell, or a femto cell. Alternatively or additionally, a macro cell may be considered a high power cell, and a small cell may be considered a low power cell. The access node in a macro cell may be referred to as a macro base station, a macro eNB, or a macro node, and the access node in a small cell may be referred to as a small cell base station, a pico base station, a femto base station, or a relay node. A cell or sector is a portion of the coverage area served by a base station. Each cell has a set of radio resources that can be associated with that cell through, for example, a unique cell identifier.
LTE may be said to correspond to aspects of Third Generation Partnership Project (3GPP) Release 8 (Rel-8) and subsequent releases.